NTAC and ITAC Process

Overview of the NTAC and ITAC Process

Gemini Time
Allocation proceeds in two phases, outlined here. Important dates for the upcoming semester are given in each Call for Proposals. This page describes the National and International Time
Allocation Committee (TAC) process.

After the Call for Proposals deadline at the end of March or September,
each National Gemini Office (NGO) collects the proposals from its
community, resolves logistical
issues and errors, and evaluates them for
technical feasibility.
Each partner then peer reviews its proposals via a National TAC
(NTAC), and creates a ranked list based primarily on scientific merit,
but also on
strategic feasibility. NTAC meetings generally occur 4-6 weeks
after the proposal deadline (late Oct/early Nov or late April/early
May). The outcomes of the NTAC meetings are ranked lists of
approved programs and recommended time allocations to fill each
partner's time allocation, for consideration by the
International TAC
(ITAC). These approved programs are forwarded to Gemini via the
"NTAC package", due ~6 weeks after the
proposal deadline each semester (generally 10-13 May or November).

The Gemini International TAC merges the
proposals to create a single combined list of programs for
execution. The ITAC only sees those proposals that are forwarded
by each NTAC. Prior to the ITAC meeting in the third or fourth week of May or November,
the ITAC chair merges
all of the forwarded programs from each partner to produce a draft
queue. The
merging process is a deterministic process that steps through each
partner's ranked program listing and distributes the time according to
each partner's share
of the total time. The draft queue is
shared with the ITAC members and with the Gemini Heads of Science
Operations who construct a preliminary telescope schedule
(incorporating engineering and commissioning work with classical time
requests and other considerations) and communicate any issues or
concerns for operations. During the ITAC meeting, the ITAC
representatives analyze the draft queue in detail; they consider
instrument availability, Target of Opportunity (ToO) programs,
duplicate observations and the distribution of programs across
different observing condition constraints, and adjust the ensemble of
proposals to construct the best "queue", both for the individual
communities and for the observatory.

The outcome of the ITAC meeting is a recommended
queue list (including scientific ranking bands), and classical
program list for execution in the coming semester. This
recommendation is forwarded to the Gemini Director for detailed
consideration. The final allocation is at the
Director's discretion and changes can be made,
although these are generally minor in nature.
The final approved list of programs is shared with the NGOs and ITAC
members, and "NGO feedback" is generated which
includes relevant comments intended for the Principal
Investigators for proposals that were forwarded to ITAC.
Within a few days of sending the NGO feedback,
the observatory notifies all successful PIs directly by email with information
about their time allocation and how to start the Phase II process. At the
same time, all the approved programs are published on the Gemini website and
the "Phase II skeletons" are made available in the Observing Database. This
generally occurs around 15 June or December.